The biggest feature of aerogel is its lightness, and its extremely high porosity makes it a solid material with the lowest thermal conductivity currently recognized. But in fact, aerogels are also known for being "brittle". Once aerogels are prepared by ordinary processes, they are easily broken into slags once they are divided and other steps. This is why aerogels are generally only used for The reason why it is difficult to use for small-scale applications (such as environmental technology, physical experiments or industrial catalysis).
It is a pity to have such excellent thermal insulation performance, but because it cannot be miniaturized, it is insulated from small-scale applications such as electronic devices. Therefore, scientists have never given up on the pursuit of small-scale aerogel preparation technology. For example, in the latest issue of the scientific journal Nature, an article from Empa researchers showed how to make 3D printed parts made of silica aerogel and silica composite with high precision.
In order to prove that the fine aerogel structure can be generated in 3D printing, the researchers printed a lotus made of aerogel
It is reported that the aerogel structure produced by 3D printing can be as thin as one tenth of a millimeter and the thermal conductivity is only half that of polystyrene, which is just below 16MW/(m·k), which is significantly lower than that of a non-moving air layer. 26MW/(m·k). At the same time, the printed silica has better mechanical properties and can even be drilled and ground on it. It can be said that the new preparation process has opened up new possibilities for the post-processing and application of silica aerogel.
As an example of the cantilever structure, the researchers printed the leaves and flowers of lotus. Due to its hydrophobicity and low density, the test object can also float on the water like its natural model
With this technology, even the smallest electronic components are relatively simple to insulate from each other. Researchers have proved through experiments that 3D printed aerogels can indeed control local "hot spots" well in temperature-sensitive components and prevent heat dissipation. In addition, good thermal insulation properties also make it useful for shielding the heat source of medical implants, ensuring that the surface temperature in contact with the human body does not exceed 37°C, thereby protecting body tissues.
The miniature custom protective cover made of aerogel can effectively shield the heat of the electronic components
Currently, Empa researchers are looking for industrial partners who want to integrate 3D printed aerogel structures into new high-tech applications.